“The right answer is for the British museum and other cultural institutions to do exactly what they do, which is to link up with other institutions around the world to make sure that the things which we have and look after so well are properly shared with people around the world.”

One is not quite sure how they intend to “properly share” the Koh-i-noor with Indians. Could Pranab-babu wear it when he opens the next session of Parliament?

Anyway I don’t think anyone is planning to ever loan the crown jewels to the erstwhile Jewel in the Crown. But this “returnism”, the misbegotten lovechild of colonialism, is interesting.

Returnism, as far as I can make out translates into something like this. I steal your laptop. Then I get it a spiffy cover and upgrade your anti-virus protection. Then when you ask for it back, I say, “Sorry, I am keeping it. I just have too many files on it now. And look how well I maintained it. I even ran a disk defragmenter on it. But hey, if you are in the neighbourhood, stop by any time and take a look for old times sake. ”

Cameron, of course, has his own logic. He could not apologise for Jallianwala because he fears that once he goes down that route, the apology list would take up the rest of his term as prime minister. Similarly once he returns the Koh-i-noor, other countries might want bits of their heritage back.

“It is the same question with the Elgin Marbles,” said Cameron as if that was a piece of unassailable British logic.

Whoa. It needs a certain chutzpah to justify one bit of imperial thievery with another bit of colonial skullduggery.

India, you can look but don’t even dream about getting the Koh-i-noor back. Getty Images

It’s true that if Britain really did start giving everything that it acquired questionably back to the rightful claimants, that would leave it with very little of its own other than some John Constable paintings of the English countryside.

It does, however beg the question, how much of the British Museum is really British?

The list of things affected by “returnism” would be long – Koh-i-noor, Elgin Marbles, Benin bronzes, Ashanti regalia, the Rosetta Stone.

The Brits are not alone of course. There’s the Nefertiti bust in Berlin, Priam’s treasure in Russia and big chunks of the Louvre in Paris.

But that does not mean “returnism” does not happen. The Louvre returned frescoes to Egypt. The Musee de l’Homme in Paris returned the Hottentot Venus to South Africa. The Kankaria mosaics were returned to the Orthodox Church in Cyprus after a court case in Indianopolis. The Met returned the Euphronius Krater to Italy in exchange for the right to display some comparable artifacts. All the art plundered during the Holocaust is supposed to be returned to the original owners. The Nazis, infamously, had special departments to seize and secure objects of cultural value. But it’s worth remembering that the Germans weren’t the only ones doing the looting. The Allies did their bit as well.

Of course, Britain’s problem is it cannot even do a cultural swap. What could it claim from its old colonies in lieu of the Koh-i-noor? It’s not like it could take back cricket.

Cameron might like to pretend that the United Kingdom is the guardian of the world’s treasures. The fact is colonisers took them because that was a way they could project their power over their subjects. As Napoleon boasted after pillaging Italy, “We now have all that is beautiful in Italy except for a few objects in Turin and Naples.”

How much these guardians of the world’s heritage truly guard them was clear to all when the Americans and British stood by after the toppling of Saddam Hussein and allowed the National Museum of Iraq to be looted. However they showed far more alacrity about securing the building of the Ministry of Oil.

As far as the Koh-i-noor goes, the diamond does have a checkered history and there are many claimants to it. In fact, “there could be other claimants besides the government of India if the "it-belonged-to-me-before-you" principle is taken to its logical conclusion,” says an editorial in the Economic Times. It suggests however that if the economic downturn in Britain gets worse, they may have to resort to selling “the family silver, not to mention the crown jewels.” So India may yet get back the Koh-i-noor.

But India also would need to get its act together. After all, Vishwa Bharati managed to lose Rabindranath Tagore’s Nobel medal because the security personnel were busy watching an Indo-Pak cricket match on television while thieves broke into the museum.

However that lapse need not prevent us from coming up with our own term to match Cameron’s returnism. How does Kohinoorism sound, Mr Cameron?